philippe_44 wrote: 
> Did you change a protocol handler to do that ? Because, by default, when
> the $formatbyte in the strm message is 'p', LMS sends raw PCM with no
> header of any kind - just a blob of bytes. The SlimProto header of strm
> contains information about sample size, rate, endianness so that the
> player knows. One bug, as we discussed before, is that on transcoded
> live streams, LMS sets rate and size @ 44.1/16 regardless and that does
> not work very well :(

Nope, LMS is untouched.

You are right, but only  when talking about 'native' (?)  raw PCM.

When transcoding, in case of pcm output (and wav is handled exactly as
pcm) LMS  try to look at the track/original file for sample rate to be
sent to players via strm message, using 44100 as default value if not
found (i.e. in case or remote streams), no matter if a resample took
place. 

Here is the bug:  

a. the transcoding command is a 'black box', LMS just know the incoming
(track, stream or file) and the outcoming (stream), no others. Somehow
correct.

b. When the outcoming stream is (raw) PCM  it has no header, then we
could not inspect it. As a  fault back we get sample rate from incoming
(or use default 44100/16 L). Debatable,  I'll preffer at least
upsampling where disabled  when output is (raw) pcm.

c. WAV is PCM, so we could not inspect the wav header  to get sample
rate. That's WRONG and here is the confusion, WAV is PCM, but is not RAW
PCM.

Not brave enought to engage a fight to change this in LMS, where it
should be, but fortunally LMS streams the result of the transcoding
command as is, with header if wav,  still using 'p' as format in the
strm message, then the workaround is to always 'transcode'  to WAV or
AIFF i(i.e. with C-3PO) and let player inspect the header.

But, accordingly to slimproto, when the format is 'p' there should be no
header in the stream (WRONG ASSUMPTION, see point c) then all the
players but Squeezelite-R2  (and from now on ralphy versions used with
-W option) trust strm message about sample rate and forget the header,
resulting they could not play server side upsampled wav (or aiff)
streams.

Hope is clearer.



____________________________________________________________
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reference and DIS Interconnect.
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